Commit sigining and message policy

We are trying to come up with contribution guidelines for Mankala, a
project we would like to bring to KDE. There is a commit policy
available at:

https://community.kde.org/Policies/Commit_Policy

a) Is it ok to ask for signed commits for a project?
b) If someone has used a coding agent, what is the best way to
acknowledge this?  Should the commit message be co-authored, or contain
an acknowledgement?  A number of KDE projects do not accept AI generated
code (primarily due to licensing and ethical concerns), but others do.
Of those that do, a few indicate co-authored and the name of the AI
tool/agent - the commit policy was written before the use of AI agents.

Benson